Vinyl ester urethane hybrid resin

The matrix resins for foamed composites include rigid pol)ruretha-nes, unsaturated polyesters, vinyl esters, and their hybrid resins, such as, unsaturated polyester-urethane hybrid resins and vinyl ester-urethane hybrid resins. The reinforcing fibers include glass fibers, carbon fibers, and organic fibers such as polyamide fiber (Kevlar, DuPont), polyamide-... 

A newly developed third class of vinyl ester resins is represented by the even higher quality VE urethanes based on bisphenol A epoxy. Here, the secondary OH groups of the VE react in polyaddition with polyisocyanates to produce urethane bridges, see Eigure 1.3. Vinyl ester urethane resins (VEU resin, vinyl ester urethane-hybrid resins) combine the good mechanical properties (stiffness) of VE resins with excellent high-temperature resistance (T approx. 220 °C and HDT approx. 210 °C) and excellent chemical resistance (the long-term durability of VEUH resin exceeds that of normal VE). 

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